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Full-Text Articles in Physical Sciences and Mathematics

Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman Jan 2006

Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman

Turkish Journal of Chemistry

A number of 1-n-alkylnaphthalenes were prepared via the respective semicarbazones. The semicarbazones were reduced by modified Wolff-Kishner reductions to give 1-n-alkylnaphthalenes in excellent yields as manageable yellow or orange viscous oils. The semicarbazones were prepared from ketones, which are the addition products of Grignard reagents to nitriles. This study offers an excellent preparative method for the synthesis of 1-n-alkylnaphthalenes from semicarbazones, via a 3-step procedure.


Synthesis And Biological Activities Of N-Alkyl Derivatives Of O-, M-, And P-Nitro (E)-4-Azachalcones And Stereoselective Photochemistry In Solution, With Theoretical Calculations, Nuretti̇n Yayli, Osman Üçüncü, Ahmet Yaşar, Murat Küçük, Nuran Yayli, Emi̇ne Akyüz, Şengül Alpay Karaoğlu Jan 2006

Synthesis And Biological Activities Of N-Alkyl Derivatives Of O-, M-, And P-Nitro (E)-4-Azachalcones And Stereoselective Photochemistry In Solution, With Theoretical Calculations, Nuretti̇n Yayli, Osman Üçüncü, Ahmet Yaşar, Murat Küçük, Nuran Yayli, Emi̇ne Akyüz, Şengül Alpay Karaoğlu

Turkish Journal of Chemistry

The N-alkyl derivatisation and photochemical dimerisation of 3 o-, m-, and p-nitro substituted 4-azachalcones (1-3) yielded 3 new o-, m-, and p-nitro substituted (E)-N-decyl-4-azachalconium bromides, (2E)-1-(2-nitrophenyl)-3-(N-decyl-4-pyridinium bromide)-2-propen-1-one (4), (2E)-1-(3-nitrophenyl)-3-(N-decyl-4-pyridinium bromide)-2-propen- 1-one (5), and (2E)-1-(4-nitrophenyl)-3-(N-decyl-4-pyridinium bromide)- 2-propen-1-one (6), and 3 new dimers in solution, (1\beta, 2\alpha)-di- (3-nitrobenzoyl)-(3\beta, 4\alpha)-di-(4-pyridinyl) cyclobutane (7), (1\beta, 2\alpha)-di-(4-nitrobenzoyl)-(3\beta,4\alpha)-di-(4-pyridinyl) cyclobutane (8a), and (1\beta, 2\beta)-di-(4-nitrobenzoyl)-(3\beta, 4\alpha)-di-(4-pyridinyl)cyclobutane (8b), stereoselectively. The monomeric compounds showed good antimicrobial activity against test micro-organisms. The most sensitive micro-organisms were Gram-positive bacteria. The monomers also showed high antioxidant activity, while the dimerisation products 7-8a,b were less active. Compound 6 was found to have similar or even …


Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi Jan 2006

Simple Synthesis Of \Alpha -Oxime Derivatives Of 2-Ketomethyl Quinolines Under Mild And Heterogeneous Conditions, Javad Safari, Mehdi Adib, Firouzeh Sheibani, Zahra Sadeghi

Turkish Journal of Chemistry

2-Ketomethyl quinolines are converted to their \alpha-oximinoketone derivatives in quantitative yields using sodium nitrite in the presence of silica sulfuric acid as nitrosating agent under mild and heterogeneous conditions.


A New Method For The Preparation Of Pyridazine Systems: Experimental Data And Semiempirical Pm3 Calculations, Di̇lek Ünal, Emi̇n Saripinar, Yunus Akçamur Jan 2006

A New Method For The Preparation Of Pyridazine Systems: Experimental Data And Semiempirical Pm3 Calculations, Di̇lek Ünal, Emi̇n Saripinar, Yunus Akçamur

Turkish Journal of Chemistry

The reactions of 4-benzoyl-5-phenyl-2,3-furandione (1a) and 4-(4-methoxybenzoyl)-5-(4-methoxyphenyl)-2,3-furandione (1b) with acyl hydrazines (2) (namely hydrazides) are reported. From these reactions, novel pyridazinone systems (3a-g) are obtained as well as the cyclization product of 3g at high temperature (4). The electronic properties and conformational parameters for these molecules, such as bond lengths, bond angles, torsion angles and atom charges, are calculated with a semiempirical PM3 method. In order to determine the mechanism of the reaction between the model furandion (R1) and formic hydrazide (R2), the electronic properties, conformational parameters and imaginary frequencies of the reactants, transition states and intermediates are calculated at …


Solvent-Free Preparation Of Primary Carbamates, Ali Reza Modarresi-Alam, Mohsen Rostamizadeh, Parisa Najafi Jan 2006

Solvent-Free Preparation Of Primary Carbamates, Ali Reza Modarresi-Alam, Mohsen Rostamizadeh, Parisa Najafi

Turkish Journal of Chemistry

Herein, we describe a simple and efficient method for the conversion of compounds containing a hydroxyl group to primary carbamates at room temperature with excellent yield and purity, and without any epimerization, in the absence of solvent.


Kinetics And Mechanism Of Oxidation Of 1,3--Butylene Glycol By Dihydroxyditellutoargentate(Iii) In Alkaline Medium, Jin-Huan Shan, Shu-Ying Huo, Shi-Gang Shen, Han-Wen Sun Jan 2006

Kinetics And Mechanism Of Oxidation Of 1,3--Butylene Glycol By Dihydroxyditellutoargentate(Iii) In Alkaline Medium, Jin-Huan Shan, Shu-Ying Huo, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of 1,3--butlene glycol (\beta - BG) by dihydroxyditelluto- argentate(III) were studied spectrophotometrically between 298.2 and 313.2 K in alkaline medium. The reaction rate showed pseudo-first order dependence in oxidant and fractional order in \ss-BG. The pseudo-first order rate constant k_{obs} increased with an increase in the concentration of OH^- and a decrease in the concentration of TeO_4^{2-} . There was a negative salt effect and no free radicals were detected. Thus, the dihydroxymonotelluratoargentate(III) species is assumed to be the active species. The activation parameters along with the rate constants of the rate-determining step were calculated.


Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman Jan 2006

Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman

Turkish Journal of Chemistry

Experimental values of rate constants for the heterogeneous transfer of electrons to methyl viologen, diquat viologen, benzyl viologen and n-butyl viologen monocations were determined. The process was studied at the surface of a platinum disk in mixtures of water with different aprotic solvents at different temperatures. Theoretical rate constants were evaluated using Marcus' equation, which also contains barrier crossing probability and nuclear frequency. A comparison was made between the theoretical and experimental values of rate constants.


Terpenic And Phenolic Compounds From Sideritis Stricta, F. Pinar Şahi̇n, Nurten Ezer, İhsan Çaliş Jan 2006

Terpenic And Phenolic Compounds From Sideritis Stricta, F. Pinar Şahi̇n, Nurten Ezer, İhsan Çaliş

Turkish Journal of Chemistry

From the overground parts of an endemic Sideritis species, S. stricta, 4 diterpenes, sideridiol (1), isosidol (2), isolinearol (3), and linearol (4); 2 flavonoid glycosides, isoscutellarein 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-\beta -D-glucopyranoside (5), and isoscutellarein 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-6''-O-acetyl-\beta -D-glucopyranoside (6); a methoxyflavone, xanthomicrol (7); and a phenylethanoid glycoside, verbascoside (=acteoside) (8) were isolated. The structures of the isolated compounds were established based on spectroscopic evidence (UV, IR, 1D- and 2D-NMR, MS).


Effect Of Surfactants On Response Of Promethazine Pvc-Membranes, Mohsen M. Zareh, Raga E. Shohiab, Mostafa Abd-El-Fatah Jan 2006

Effect Of Surfactants On Response Of Promethazine Pvc-Membranes, Mohsen M. Zareh, Raga E. Shohiab, Mostafa Abd-El-Fatah

Turkish Journal of Chemistry

The effect of surfactants (cationic, anionic and non-ionic) on the performance of plastic membrane promethazine electrodes was studied. Three electrodes with membranes containing either sodium tetraphenylborate, sodium tetraphenylborate + 18-crown-6, or 18-crown-6 were prepared. The cationic and the anionic surfactants exhibited potential shifts and a super-Nernstian slope of the calibration graphs. The non-ionic surfactant did not cause alterations in the calibration graphs. The effect of surfactants' concentrations was investigated. The performance characteristics of these electrodes were studied. The slopes of the calibration graphs of the 3 electrodes were 54.4, 54.9 and 48.4 mV/decade. The rectilinear ranges were 2 x 10^{-5}-10^{-2}, …


Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz Jan 2006

Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz

Turkish Journal of Chemistry

Novel plasticized polymeric membrane (PPME) and coated platinum wire (CPWE) electrodes based on 1,4,7-trithiacyclononane and oleic acid, as a good lipophilic additive for highly selective determination of Ce^{3+} ions, have been developed. The electrodes exhibit a Nernstian slope of 19.4 mV/decade (for both electrodes) over a wide Ce^{3+} ion concentration range, from 5.0 \times 10^{-6}-5.0 \times 10^{-2} M and 1.0 \times 10^{-7}-1.0 \times 10^{-2} M for PPME and CPWE, respectively. The limits of detection were 3.5 \times 10^{-6} and 8.0 \times 10^{-8} M for PPME and CPWE, respectively. The electrodes possess a fast response time of 15 s, can be …


The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin Jan 2006

The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin

Turkish Journal of Chemistry

Acetal of warfarin acid has been synthesized via a hemi acetal intermediate and structurally characterized by X-ray diffraction. The crystal structure shows that the title compound was formed by the hydrolysis of warfarin acid in methanol at pH 3, with space group P2_1/n and unit cell parameters a = 5.859 (17), b =16.745 (5), c = 16.402 (5) Å, \alpha = 90.00; \beta = 94.853 (4), and \gamma = 90.00°.


Template Synthesis And Structural Characterization Of Homo Binuclear Chromium(Iii), Manganese(Iii), Iron(Iii), Cobalt(Iii), And Ruthenium(Iii) Complexes With Octaazamacrocyclic Ligands, Vinod K. Sharma, Shipra Srivastava Jan 2006

Template Synthesis And Structural Characterization Of Homo Binuclear Chromium(Iii), Manganese(Iii), Iron(Iii), Cobalt(Iii), And Ruthenium(Iii) Complexes With Octaazamacrocyclic Ligands, Vinod K. Sharma, Shipra Srivastava

Turkish Journal of Chemistry

The Schiff base octaazamacrocyclic ligands derived from primary diamines and 3,6-dimethyl/diphenyl-4,5-diazaocta-3,5-diene-2,7-dione, and their binuclear complexes [M_2LCl_4]Cl_2 [M = Cr(III), Fe(III), Co(III), or Ru(III)] and [Mn_2L(AcO)_4](AcO)_2 were synthesized by template condensation reactions. Attempts to synthesize the corresponding metal-free macrocyclic ligands did not prove successful. The overall geometry and stereochemistry of these complexes were elucidated by elemental analyses, magnetic susceptibilities, electronic spectra, infrared spectra, molar conductance measurements, ^1H NMR, and thermogravimetric analysis. All the trivalent metal ion complexes appear to be 1:2 electrolytes. An octahedral geometry is proposed for all the complexes.


The Effect Of Acid Digestion On The Recoveries Of Trace Elements: Recommended Policies For The Elimination Of Losses, Güler Somer, Arzu Nakişci Ünlü Jan 2006

The Effect Of Acid Digestion On The Recoveries Of Trace Elements: Recommended Policies For The Elimination Of Losses, Güler Somer, Arzu Nakişci Ünlü

Turkish Journal of Chemistry

Digestion of biological materials is very important for trace element determinations. Although the microwave technique is mostly used, there are cases where open wet digestion is needed. This study examined the optimum conditions for the minimum loss of trace elements during the wet digestion of a sample. The effect of acid composition and digestion time for about 21 ions was investigated. The trace element concentrations were determined by differential pulse polarography. For the digestion procedure, a HClO_4-HNO_3 mixture was used for the first step and, after its evaporation (60 min), HCl was added as the second step, since in some …


Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren Jan 2006

Hydrothermal And Microwave-Assisted Synthesis Of Boroarsenate, Baso_4, Abdulhadi̇ Baykal, Ayten Evren

Turkish Journal of Chemistry

BAsO_4 was previously synthesized by solid-state reactions at 800 °C and was characterized by X-ray powder diffraction. Now, we succeeded in preparing BAsO_4 from H_3BO_3 and As_2O_5 using hydrothermal synthesis by heating at 160 °C for 3 days (a single-phase product) and using microwave-assisted synthesis, which takes only 5 min to transform a solid mixture of As_2O_5 and (NH_4)_2B_4O_7.4H_2O into the crystalline titled compound (a single-phase product). The crystallinity of the products is higher than that of the solid-state synthesized product given in the literature. Its X-ray powder diffraction patterns, and both Raman and IR spectra were in good agreement …


Prediction Of Acidity Constants Of Thiazolidine-4-Carboxylic Acid Derivatives Using Ab Initio And Genetic Algorithm-Partial Least Squares, Ali Niazi, Saeed Jameh Bozorghi, Davood Nori Shargh Jan 2006

Prediction Of Acidity Constants Of Thiazolidine-4-Carboxylic Acid Derivatives Using Ab Initio And Genetic Algorithm-Partial Least Squares, Ali Niazi, Saeed Jameh Bozorghi, Davood Nori Shargh

Turkish Journal of Chemistry

A quantitative structure-property relationship study is suggested for the prediction of the acidity constants of some thiazolidine-4-carboxylic acid derivatives in aqueous solution. Ab initio theory was used to calculate some quantum chemical descriptors, including electrostatic potentials and local charges at each atom, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies, etc. Modeling of the acidity constant of thiazolidine-4-carboxylic acid derivatives as a function of molecular structures was established by means of the partial least squares algorithm. The subset of descriptors, which resulted in a low prediction error, was selected by genetic algorithm. This model was applied …


Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia Jan 2006

Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia

Turkish Journal of Chemistry

Acrylamide (AAm) monomer was directly grafted onto chitosan using ammonium persulfate (APS) as an initiator and methylenebisacrylamide (MBA) as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-poly(acrylamide) (chitosan-g-PAAm) with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution (0.15 mol/L NaCl, CaCl_2 and AlCl_3) was examined. Swelling capacity …


Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik Jan 2006

Synthesis Of 1-Cyclohept-1,2-Dien-1-Yl Benzene From 1-(2-Iodo-, Chlorocyclohept-1-En-1-Yl)Benzene And 1-(2-Iodo-, Chlorocyclohept-2-En-1-Yl)Benzene: Its Trapping With Diphenylisobenzofuran, Mustafa Ceylan, Yakup Budak, Murat Ulukaya, M. Burcu Gürdere, Esra Findik

Turkish Journal of Chemistry

The key compounds vinyl iodides 12a and 13a, for the generation of 1-cyclohept-1,2-dien-1-ylbezene (1), were synthesized from cycloheptanone (5). Bromobenzene was converted to the Grignard reagent, which was condensed with 5. Dehydration of alcohol 6 gave alkene 7. Hydroboration of 7 followed by oxidation with PCC afforded ketone 9, which was converted to hydrazone 10. Treatment of 10 with iodine resulted in the formation of 12a and 13a. The other precursors, 12b and 13b, were synthesized from the reaction of 9 with PCl_5. Reactions of 12a, b and 13a, b with KOtBu in a sealed tube at 185 °C gave …


Analysis Of Nanoparticle Transmission Electron Microscopy Data Using A Public- Domain Image-Processing Program, Image, Gerd H. Woehrle, James E. Hutchison, Sai̇m Özkar, Richad G. Finke Jan 2006

Analysis Of Nanoparticle Transmission Electron Microscopy Data Using A Public- Domain Image-Processing Program, Image, Gerd H. Woehrle, James E. Hutchison, Sai̇m Özkar, Richad G. Finke

Turkish Journal of Chemistry

The need to easily and quickly count larger numbers of nanoparticles, in order to obtain statistically useful size and size-distribution data, is addressed via the use of a readily available, free, public-domain program for particle counting, NIH-Image (and 2 others derived from it, Scion Image and Image J), collectively referred to herein as Image. The best protocols that we have found useful for the use of Image are reported; both appropriate as well as problematic applications of Image are then illustrated with a series of TEM images of Ir(0), Pd(0) and Au(0) nanoclusters. Methods to detect and image nanoclusters with …


Cyclic Triterpenoid Saponins From Campanula Lactiflora, Nuretti̇n Yayli, Asu Usta, Ahmet Yaşar, Osman Üçüncü, Canan Güleç, Mustafa Küçükislamoğlu Jan 2006

Cyclic Triterpenoid Saponins From Campanula Lactiflora, Nuretti̇n Yayli, Asu Usta, Ahmet Yaşar, Osman Üçüncü, Canan Güleç, Mustafa Küçükislamoğlu

Turkish Journal of Chemistry

Two cyclic natural compounds, 3\beta-O-[\alpha-L-rhamnopyranosyl- (1 \to 2)-\beta-D-glucopyranosyl]-13\alpha,14\alpha-epoxy-8\alpha,12\beta, 15-trihydroxy-(17E,21E)-17,21-campanuldien-6'(30)-olide, called lactifloroside A, 1, and 3\beta-O-[\beta-D-glucopyranosyl-(1 \to 2)-\beta-D-glucopyranosyl]- 13\alpha,14\alpha-epoxy-8\alpha,12\beta-dihydroxy-(17E,21E)-17,21-campanuldien- 6'(30)-olide, called lactifloroside B, 2, were isolated for the first time from Campanula lactiflora and their structures deduced by high field 1D and 2D 400 MHz NMR, FT-IR, HPLC, GC-MS, (+/-) LC-MS/MS and (+) FAB-MS spectra. The aglycones of the 2 saponins were named 13\alpha,14\alpha-epoxy-3\beta,8\alpha,12\beta,15-tetrahydroxy-(17E,21E)- 17,21-campanuldien-30-oic acid and 13\alpha,14\alpha-epoxy-3\beta,8\alpha, 12\beta-trihydroxy-(17E,21E)-17,21-campanuldien-30-oic acid, and designated as campanuloic acid and 15-deoxycampanuloic acid, respectively.


First- And Second-Derivative Spectrophotometry For Simultaneous Determination Of Copper And Cobalt By 1-(2-Pyridylazo)-2-Naphthol In Tween 80 Micellar Solutions, Habibollah Eskandari, Ali Ghanbari Saghseloo, Mansour Arab Chamjangali Jan 2006

First- And Second-Derivative Spectrophotometry For Simultaneous Determination Of Copper And Cobalt By 1-(2-Pyridylazo)-2-Naphthol In Tween 80 Micellar Solutions, Habibollah Eskandari, Ali Ghanbari Saghseloo, Mansour Arab Chamjangali

Turkish Journal of Chemistry

1-(2-Pyridylazo)-2-naphthol (PAN) has been used for the simultaneous determination of copper and cobalt at trace levels. PAN at pH 1.89 forms red and green complexes with copper and cobalt, respectively, which are soluble in aqueous Tween 80 micellar media and are stable for at least 3 days. Under optimum conditions, calibration graphs were obtained for individual determination of copper and cobalt by zero- and first-derivative spectrophotometry and for simultaneous determination by first- and second-derivative spectrophotometry. Zero-crossing first-derivative spectrophotometry at 555 and 581 nm for cobalt and copper was used for the simultaneous determination, respectively. The second derivative method at 577 …


A Novel Alkaloid From Stapelia Hirsuta, Marwan Shabana, Mariam Gonaid, Maha Mahmoud Salama, Essam Abdel-Sattar Jan 2006

A Novel Alkaloid From Stapelia Hirsuta, Marwan Shabana, Mariam Gonaid, Maha Mahmoud Salama, Essam Abdel-Sattar

Turkish Journal of Chemistry

A novel alkaloid (1,8,8-trimethyl-5,8-dihydro-1H-pyrano[3,4-b]pyridine-4,6-dione) was isolated from the chloroformic traction obtained from the total alcoholic extract of the aerial parts of Stapelia hirsuta L. In addition, apigenin, luteolin and \beta-sitosterol-3-O-\beta-D- glucopyranoside were also isolated.


Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya Jan 2006

Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

3,6-Bis(dimethylamino)acridine(hexamethylbenzene)dichlororuthenium(II) was used as a tricyclic heteroatomic monomer to prepare polyimides from the corresponding dianhyrides by solution condensation. The ruthenium complex monomer was synthesized starting from [RuCl_2(HMB)]_2 and 3-6-bis(dimethylamino)acridine. The polymers had inherent viscosities of 1.77 to 2.11 and were soluble in most polar solvents. The glass transition temperatures were in the range of 204 to 298 °C and the 10% weight loss in the range of 506-626 °C, depending upon the structure of the dianhyride monomer. The catalytic activity of the polyimides tested in a hydrosilylation reaction of acetophenone was up to 90%. Leaching of ruthenium into the reaction …


Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş Jan 2006

Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş

Turkish Journal of Chemistry

The title compound, C_{16}H_{12}N_2S_2, crystallizes in the monoclinic space group P2_1/n with Z = 4, a = 8.950 (5) Å, b = 9.141 (5) Å, c = 17.429 (5) Å and \beta = 93.638 (5)°. The benzimidazole ring is essentially planar. The crystal structure is stabilized by intermolecular C---H ... N and C---H ... \pi contacts.


Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle Jan 2006

Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle

Turkish Journal of Chemistry

A new class of spiro-triazoles (4a-m) were synthesized from the reaction of corresponding nitrilimines 2 with substituted heterocyclic benzoylhydrazones 3 in good yields. The spectral data of the new synthesized compounds are in full agreement with their molecular structure.


Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada Jan 2006

Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada

Turkish Journal of Chemistry

Six new 3-pyrrolin-2-one derivatives were synthesized via the condensation reaction of amino acid esters (2a-f) with 2,5-dimethoxy-2,5-dihydrofurane (1) in acidic medium. This simple one-pot reaction furnished the corresponding pyrrolinones (3a-f) in acceptable yields.


Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci Jan 2006

Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci

Turkish Journal of Chemistry

1,4-Dihydroxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)- dione (7) was synthesised from hydroquinone and glutaric acid chloride via an acylation reaction. The reaction of dione (7) with bromine followed by treatment with NEt_3 gave homonaphthazarin 8 as well as the brominated derivatives 9 and 10. Reduction of 1,4-dimethoxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)-dione (16) with LiAlH_4 gave 2 isomeric alcohols, 17 and 18. Reaction of these alcohols with SOCl_2 followed by HCl elimination with NEt_3 afforded dimethoxybenzocycloheptatriene 19 as the sole product. For the synthesis of the isomeric cycloheptatriene 20, the double bond in 19 was isomerised with KOt-Bu.


Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean Jan 2006

Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean

Turkish Journal of Chemistry

Acrylic dispersions based on polyaniline were obtained and characterised. The polyaniline was obtained by chemical polymerisation of aniline in different organic acid containing phosphorous, in the presence of ammonium-peroxidisulphate as oxidant agent. The blends were obtained by mechanical dispersion of polyaniline in commercially available acrylic resin. The flow behaviour of these dispersions at different shear rates was studied. Furthermore, the resulting acrylic dispersions were analysed by IR spectroscopy, and were characterised in terms of their electrical resistance and rheological behaviour


Organotin (Iv) Derivatives Of 1-Ethyl-1,4-Dihydro-7-Methyl-4-Oxo- 1,8-Naphthyridine-3-Carboxylic Acid (Nalidixic Acid): Synthesis, Structural Elucidation And Biological Activities, Sajjad Ahmed, Moazzam Hussain Bhatti, Saqib Ali, Fiaz Ahmed Jan 2006

Organotin (Iv) Derivatives Of 1-Ethyl-1,4-Dihydro-7-Methyl-4-Oxo- 1,8-Naphthyridine-3-Carboxylic Acid (Nalidixic Acid): Synthesis, Structural Elucidation And Biological Activities, Sajjad Ahmed, Moazzam Hussain Bhatti, Saqib Ali, Fiaz Ahmed

Turkish Journal of Chemistry

Organotin carboxylates of the general formulae R_2SnL_2 and R_3SnL, where R = CH_3, n-C_4H_9, C_6H_5, CH_2C_6H_5 and L = 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid (nalidixic acid), have been prepared. These compounds were characterized by FT-IR, mass and multinuclear NMR (^1H, ^{13}C and ^{119}Sn) spectroscopy. The geometry around the tin atom is compared both in solution and in solid state. These compounds were also screened for their antifungal and antibacterial activities.


Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz Jan 2006

Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz

Turkish Journal of Chemistry

Surface modification of glass beads with a self-assembled monolayer of (3-Aminopropyl)-triethoxysilane (APTES) was investigated. Characterisation of the self-assembled monolayer was confirmed by a reaction between amine terminal groups and thionylchloride of Rhodamine-B dye using fluorescence microscopy. Quantitative 3-dimensional profiling was obtained for all modification processes by converting microscopic images to numerical values. The reaction steps were also analysed using infrared spectroscopy (FTIR).


Surface Properties And Catalytic Performance Of Pt/Prsrcoo_4 Catalysts For No Reduction By Co, Hua Zhong, Xirui Zeng Jan 2006

Surface Properties And Catalytic Performance Of Pt/Prsrcoo_4 Catalysts For No Reduction By Co, Hua Zhong, Xirui Zeng

Turkish Journal of Chemistry

Perovskite-type Pr_{2-x}Sr_xCoO_{4\pm \lambda} mixed oxides were prepared by different calcination temperatures and were investigated by XRD, BET, TPD, TPR and XPS methods. These catalysts possess high catalytic activities towards the NO reduction by CO, and the activity of the PrSrCoO_4 catalyst prepared by calcining at 750 °C is the best among these samples. This is explained in terms of its greater oxygen vacancies and larger BET surface areas. The influence of modification by a suitable amount of Pt-doping on the surface properties and catalytic activity for NO reduction by CO was studied. The results show that the Pt-modified PrSrCoO_4 catalysts …